We have investigated the spatial dependence of the longitudinal piezoelectric stress constant e of PVF . Experiments were performed on a series of no.minally identical brass-backed PVF longitudinaF wave t~ansducers in water using commercial PVF7 film. Computer programs were designed t6 predict the performance of the transducers as a function of e (Z) , the thickness mode piezoelectric stress co...

The ICP algorithm and its derivatives is the de facto standard for registration of 3D range-finder scans today. This paper presents a quantitative comparison between ICP and 3D NDT, a novel approach based on the normal distributions transform. The new method addresses two of the main problems of ICP: the fact that it does not make use of the local surface shape and the computationally demanding...

The inspection of aerospace materials such as composites, honeycomb structures, ceramics and GLARE has been the subject of many studies in the NonDestructive Testing and Evaluation (NDT&E) community. Active thermography techniques have shown to be an interesting alternative or complementary to other classical NDT&E techniques. Nevertheless, the different techniques perform differently depending...

Spatial variability of concrete is an important characteristic, which qualifies the non-homogeneity of concrete properties within structural components. Assessing it can be of great interest for damaged areas localization and for reliability analysis of structures. A two-stage experimental program was carried out using non-destructive testing (NDT) on laboratory concrete slabs in outdoor enviro...

This review paper deals about the main optical NDT (Non-Destructive Testing) method known as, electronic speckle Interferometry. Optical metrology is a field of physics, which includes theoretical and experimental methods to estimate physical parameters, using the light wavelength as fundamental scale. Most of the modern industries need quick and reliable measurement methods for measuring defor...